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Mr Trash Wheel Jr.

This is a prototype that is aimed at removing rubbish and litter from various locations like oceans and rivers. As a team, we took inspiration from Mr. Trash wheel which is located in Baltimore, Maryland. Our prototype includes a conveyor belt which is the main mechanism behind how rubbish is collected. The conveyor belt is installed at an angle which allows rubbish to be collected while allowing excess water to seep through. The trash is then lead into a box which floats on top of the water. This is highly convenient as plastic bags can be easily installed and interchangeable between each trash collecting rounds. The conveyor and the box are further reinforced by heavy duty PVC and metal L-Frames. This entire structure is then placed on top of a thick and sturdy foam material which allows the entire prototype to float on the water surface.

Step 1: Demo

The prototype functions by floating on the water and having the tip of the conveyor belt under the water. This allows it to catch any trash that may be flowing just beneath the surface of the water. The belt is also supported be heavy duty plastic ridges that allow objects like cans and bottles to stay in place without slipping around on the conveyor belt. A motor is attached to the upper portion of the conveyor belt so it stays out of the water. The motor consists of a wheel which pushes the wheel that is connected to the belt. The motorized system is powered by a wall socket.

List of materials and machines

78 x 56 x 18 cm plastic box (this can be varied depending on the size of the conveyor belt)

Conveyor belt

Metal L-frames

PVC pipes PVC pipe connectors

Floating foam boards

Working motor with rotating wheels

Power source (wall socket, generator)

Step 2: Design

Scale 1/10 cardboard prototype, Redesign, Buying Parts: [Isaac]

Before creating the final prototype, we decided to create a 1/10 cardboard prototype to get the feel of the size and the looks of the final prototype. This cardboard prototype allowed us to also reconsider many factors for our final design, such as the material we should be using and the dimensions as a whole. When building the prototype we realized many things, a project that has the dimensions of a meter by meter by 0.5 meter would be not only hard to lift and transport but also trying to make it float would be a challenge. Another issue with this idea was that a source of power would be an issue since originally we were going to use solar panels, but looking at the costs and the power output, we felt it would not be effective for this project. Which is why we needed to redesign some parts for our final prototype. To solve our first problem, we had to redesign the frame, this required a lot of measuring, planning and building. Which we finally decided to scale down the design to around a meter by 0.8 meters by 0.3. To solve our second problem we decided to make a long water-proof extension to use as our power source. To redesign the prototype we also needed to buy many parts, so we used an app called “Carousell”, which allows users to sell and buy items within a few clicks. We also went to IKEA and Sham Shui Po to buy our materials required.

Step 3: Frame

We created the back part of the prototype using PVC because it is light and is able to support the box. But the front part of the frame is built out of metal because it better supports the conveyer belt and gives it more s

Step 4: Motor

We did not build the motors, but instead, we detached it from a nonfunctional machine from the workshop at MakerBay and attached a small wheel to the motors which would have a good grip for the rim of the treadmill.

Step 5: Assembly

When putting all the parts together, we used a special glue which is made specifically for attaching the PVC’s together. Once the glue is on the PVC it will help mend both ends together and stay stuck. It provides great strength and stability. We also had to find a way to attach the insulated boards either the metal frame or the PVC frame because we need the prototype to be stable while it's in the water and not slide and sink. In the end, we decided to use several zip-tie to tie the insulated foam board to the PVC on four different angles so that it provides all-around stability.

Step 6: Frame 2

At the very beginning, we planned to use PVC as our whole frame protection, but the front frame where the motors and the treadmill are would not work as well. This is due the amount of weight that the motors and treadmill are weighing on the PVC pipes, which bends it and isn’t protective enough. Therefore we redesigned it and used metal frames instead of PVC for the front, so it gives the motors and treadmill better stability.

Step 7: Ridges

For the ridges, we discussed to used aluminium as a way to collect trash, but after further discussion with teachers and mentors, we came to a conclusion to use semi-hard plastic which is durable and light. We want the ridges to be as light as possible because we don’t want to add further weight to the front, as it is already heavy enough.

Step 8: Flotation

For the floatation aspect of our system, we used and shaped long pieces of insulated boards. The 85 by 65 piece of insulated board. We placed this board under the entire system apart from a few inches of the end tip of the treadmill, however, made some adjustments. Due to the teeth and ridges on the treadmill, we cut a rectangular hole to accommodate the paths of these ridges. Along with the insulated boards, the PVC pipes we used in the frame formation of the holding the entire system was a help in floatation. Due to the seals on the ends of the PVC, the lightness, as well as buoyancy, reduced the stress on the foam board. One major concern we have in regards to putting our system in the water was the balancing issues. Due to the large engine and treadmill being placed on the upper right side of the contraption, a lot of focused weight was on that point. We were able to use a standard sandbag to distribute weight evenly as well as keep the system afloat.

Step 9: Reinforcements

After the assembly of all pieces, and the screw and glue of the placements, reinforcements are needed. Although our group wasn't sure whether glueing already nail down points would be of any help however we decided to go ahead and glue down the nails anyway. We decided that not only will this provide additional reinforcements without adding a lot of additional weight, it would also water seal most of our system.

Step 10: Test

Due to the heavy weight of our device, placing the device in the water is a difficult task. By holding the device heavy side up and lowering the light side down, we found this method provides the most control. The prototype we build had many limitations so there were many conditions that needed to be right. For one, we found an electrical socket that was used to power our machine. Secondly, due to the lack of manoeuvrability of the device as well as the lack of current, the trash needed to be manually pushed into the direction of the ridges to be then picked up. However, the goal of this test was to prove the concept of the device and was achieved.

Step 11: ​Conclusion/Feedback From Professionals:

Our prototype was the most basic of it’s kind and was just a proof of concept. As well as gained from the feedback, there were many clear steps in pushing this system forward. The first and large step will make the system as self-sustaining and autonomous as possible. This will require the implementation of energy sources such as solar panels as well as a system where the trash can be sorted with. The feedback that our group received was a suggested anchored application. It was recommended that our system will provide the greatest benefit in an anchored position where trash is accumulated due to tides and currents where it can then be collected.

Step 12: Special Thanks (Credits)

Introduction [Cesar] It is estimated that “by 2050, 99 % of seabirds could be eating plastic”. How did we get here?Hong Kong is known for a consumer culture and a low rate of recycling. The South China Morning Post reports that in 2017, “the amount of waste per person disposed daily has increased, while the waste recovery rate decreased. From 2015 to 2016, waste disposed went up (from 1.39 to 1.41kg), while waste recovered went down (from 35.4 to 34 per cent). That’s the worst performance in a decade.”. The situation is already worrisome, and it is only worsening despite the efforts of the local non-profit organisations and educational institutions. When the conditions are “right”, Hong Kong coast fills up with floating debris. What can we do about it? Picking up marine litter by hand is ineffective, tiring and does not match the magnitude of the problem at hand. Of course, we should produce, consume and dispose of less plastic, yet we need better technologies to collect the plastic that is already in the ocean. We are students from the CDNIS (Canadian International School of Hong Kong) and our school is school located very near the Aberdeen Harbour. Some days, the harbour fills up with a lot of marine litter. During a week long Impact Invention program with MakerBay makerspace, we came up with 3 different designs to collect marine litter for our specific conditions.